topography

geography

Arctic tundra: the arctic tundra extends from the North Pole to the taiga forests in Alaska, Russia and Canada (the tundra biome).Alpine Tundra: Alpine tundra is part of mountainous regions worldwide and exists above the treeline where conditions will not support trees and large vegetation (the tundra biome).

permafrost

Permafrost is a layer of permanantly frozen soil. This is a very important part of the tundra ecosystem; for most of the year it remains frozen, but in the warmer months the very top layer thaws and melts to form shallow lakes and bogs that can support the expolsion of life during the short summer (National Geographic). Arctic tundras have this freeze-thaw layer with a permanent underlying layer of permafrost. Alpine tundras have a freeze-thaw layer, but not permafrost (Miriam- Webster). This permantely frozen soil is what creates poor drainage and thus forces the development of lakes and bogs. This unique feature of the tundra is what makes it one of the major carbon 'sinks' on planet Earth (an area that takes in more carbon dioxide than it produces). During the short summer tundra's plants take in carbon dioxide during photosynthesis. Plants normally give off carbon dioxide after they die and decompose, but because of the freezing winter temperatures in the tundra plants don't decompose when they die. These plants freeze within the permafrost and thus trap and remove large quantities of carbon dioxide from the atmosphere (Blue). However, with global warming, the carbon trapping ability of the permafrost is in danger of vanishing. It is believed that 15-30% of the Earths carbon is trapped within the permafrost, but as the Earth warms and the permafrost melts deeper, the frozen plants decompose and release the gas into the atmosphere and turns the permafrost into a carbon contributer, rather than a carbon sink (National Geographic). The cold climate also affects the soil composition. Because there is very little decay and decompositin, the soil is fairly nutrient poor (Blue).